Mobile video broadcast is a new mobile service that transfers video contents to mobile users via broadcast networks, mobile communication networks, and mobile terminals.
The electronic service guide (ESG) is an important application of the mobile video broadcast service. ESG data provides a direct user interface and access guide for a user to view data related to different services. With an ESG, a user can browse the video channel and program list, browse the price list, select and buy one or more items in the price list, and log in to a website to browse web pages. ESG data includes the ESG and fragments, where the ESG is composed of different types of fragments according to their internal logical relations. Normally, information of one program is related to multiple fragments so that ESG data is processed on both the server and terminal sides using a fragment based mechanism.
A user may obtain ESG data in multiple modes, one of which is to obtain ESG data via an interactive channel. In the prior art, TV-Anytime (TV-A) and broadcast (BCAST) protocols define a method for transporting ESG data via the interactive channel.
FIG. 1 shows a signaling interaction procedure for transporting the ESG via an interactive channel. As shown in FIG. 1, the signaling procedure includes the following steps:
Step 101: A terminal sends an ESG request to an ESG server.
Step 102: The ESG server sends a response to the terminal, the response carrying all fragments related to the ESG requested by the terminal.
Now, the procedure for transporting the ESG via an interactive channel is completed.
After a period of time, some fragments stored in the terminal may already be updated in the server. At this time, the terminal wishes to update the fragments stored in the terminal locally. In the prior art, the terminal can only send another ESG request to the ESG server according to the method shown in FIG. 1 and the ESG server will send all fragments related to the ESG requested by the terminal to the terminal. Actually, however, it is possible that no fragments stored in the terminal are updated in the server or most fragments stored in the terminal are consistent with the fragments stored in the server without being updated. It is unnecessary for the ESG server to send fragments that are not updated to the terminal. The ESG update method in the prior art is not specific, therefore unnecessary transport exists in an ESG update process, which adds to the processing load of the terminal.